1. Field of the Description
The present description relates, in general, to design of structural support elements or frames for robots or robotic figures, and, more particularly, to a structural frame (and robots or robotic figures including such a structural frame) for use in sections or segments (or subassemblies) of robots or robotic figures that have an outer covering and that are animated or have motion during operations of the robot or robotic figure. For example, the robot section or segment may be covered with skin, a layer of fur, a feathered layer, and so on that moves with changes in the shape of the underlying structural frame.
2. Relevant Background
There is an increasing use of robots (or robotic figures) in a wide variety of applications in which it is desirable for the robotic figures to have a natural look and to also move in a natural and expected manner. To this end, robotic figures often are designed to include an outer covering such as a layer of skin when the robotic figure is human or human-like or a layer of fur or coat of feathers when the robotic figure is an animal or a bird. These outer coverings generally will be formed of materials that are flexible so that they can move with the underlying robotic components such as a structural support element or frame for the outer covering.
A design challenge for such robotic figures is how to move the underlying robotic components or mechanisms while also providing movement of the outer covering that appears natural or organic. For example, the robotic figure may take the form of an animal with a fur coat or a humanoid with a skin layer, and it is desirable for the fur coat or skin layer to move in an expected and typically smooth manner with the underlying robotic figure components that may be used to represent the figure's skeletal structure and musculature.
One problem facing designers of robotic figures is how to make a support structure or frame for a character that allows for bend and flexibility and still looks realistic when an outer coating is applied. Further, the support structure or frame needs to stand up to the rigors of extended and repeated use in many applications without requiring frequent maintenance. Additional design problems arise when there is a need for the robotic figure to be relatively small such as to provide an animated character that could be handheld. In such cases, there is extremely limited space in the body for mechanical and costuming elements, and there is a desire to design bodies including structural frames that move realistically but have the smallest form factor that is practical and that are relatively low weight in their construction to reduce actuation forces required to animate the structural frame.
Existing designs for structural frames of covered robotic figures involve use of a rigid metal frame. The metal frame may include springs, cables, and other elements to assist in providing desired movements. This metal frame is positioned within an outer covering, which can be challenging in itself as it may be like stuffing the metallic frame into a tight sock or sleeve. There are a number of problems with existing metal frames. These frames are heavy such that significant amounts of actuation force is required for animation. Further, it can be difficult to control the deformation of the metal frame components such that movement of the outer covering can have an unnatural appearance. The metal frame may have sharp edges that can be seen through the outer covering and can cause excessive wear during prolonged and repeated use of the robotic figure. Additionally, metal robotic frames can produce unwanted sounds during operations such as squeaking, rattling, clanking, and the like that typically are not associated with the character being presented by the robotic figure. The complexity of many existing frames makes their use impractical when small space is a design factor for the segment or section of the robotic figure.
Hence, there remains a need for improved structural frames for robots or robotic figures. Preferably, the new structural frames would be relatively light, would have small form factors (e.g., be useful in handheld-type robotic figures), would produce little or no noise when deformed, and would deform in a more organic and natural manner while being long lived even under repeated deformation over long periods of time.